In its response to an Aug. 5 ruling by a CPUC administrative law judge, Rosemead-based Edison said only one of the 10 communications were reportable and the agency actually was apprised of that contact.

The ruling by PUC Administrative Law Judge Melanie Darling concerned communications between March 26, 2013, and June 17, 2014, when officials were discussing how to divvy costs of retiring the nuclear plant on the northern San Diego County coastline.

The violations, if eventually upheld, could result in fines of up to $50,000 per day per offense, according to the PUC.

Edison, the operator and majority owner of the plant, its partner, San Diego Gas & Electric, and ratepayer groups reached an agreement last year on the shares of the costly shutdown process that the utilities and customers would bear.

It was later discovered that an Edison executive and former Commissioner Michael Peevey had a conversation about the then-proposed deal while at an industry conference in Poland, leading to accusations that the deal was fixed.

Peevey later resigned.

A consumer group and a state agency that represents ratepayers, both of which signed onto the agreement, recently withdrew their support.

An investigation later pinned the blame on poorly designed steam generators from Mitsubishi Heavy Industries of Japan installed a couple of years earlier.

SCE executives eventually decided to retire the reactors instead of pursuing a costly restart process.

"SCE strives to comply with the commission's rules by exhibiting the highest standards of ethics and integrity," said Pedro Pizarro, president of SCE. "SCE believed the March 2013 meeting was not reportable under the commission's rules, based on the information provided at the time. It was not until early 2015 that SCE learned additional information that indicated a report should be filed."

He said that communication was reported to the CPUC on Feb. 9 of this year.